It is possible to specify an interface (and therefore an FLM) to be used
for each component (bld.inf) in a build in addition to the normal target
FLMs used to create the binaries.

This is done by setting the variable "INTERFACE.component" in the build
configuration to the name of the required interface.

Operations can then be performed on a per-component basis. An example of
how to use this can be seen in the test file,

$SBS_HOME/test/smoke_suite/flm_extension.py

which uses the following files to set-up and perform a "documenting" build,

$SBS_HOME/test/smoke_suite/test_resources/docs/docs_build.xml
$SBS_HOME/test/smoke_suite/test_resources/docs/component.flm
$SBS_HOME/test/smoke_suite/test_resources/docs/target.flm

By default the variable "INTERFACE.component" is set to "" and no extra FLM
is included.
